From 46685d1a9521054fa3a7a352f6bb54166cd5b2c5 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 19 Jun 2017 09:26:24 +0200 Subject: [PATCH] blk-mq: don't bounce by default For historical reasons we default to bouncing highmem pages for all block queues. But the blk-mq drivers are easy to audit to ensure that we don't need this - scsi and mtip32xx set explicit limits and everyone else doesn't have any particular ones. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-mq.c | 5 ----- drivers/block/virtio_blk.c | 3 --- drivers/block/xen-blkfront.c | 3 --- 3 files changed, 11 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 41e3aeb51c9a..05dfa3f270ae 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2349,11 +2349,6 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, blk_queue_make_request(q, blk_mq_make_request); - /* - * by default assume old behaviour and bounce for any highmem page - */ - blk_queue_bounce_limit(q, BLK_BOUNCE_HIGH); - /* * Do this after blk_queue_make_request() overrides it... */ diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index e59bd4549a8a..0297ad7c1452 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -720,9 +720,6 @@ static int virtblk_probe(struct virtio_device *vdev) /* We can handle whatever the host told us to handle. */ blk_queue_max_segments(q, vblk->sg_elems-2); - /* No need to bounce any requests */ - blk_queue_bounce_limit(q, BLK_BOUNCE_ANY); - /* No real sector limit. */ blk_queue_max_hw_sectors(q, -1U); diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index ac90093fcb25..c852ed3c01d5 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -953,9 +953,6 @@ static void blkif_set_queue_limits(struct blkfront_info *info) /* Make sure buffer addresses are sector-aligned. */ blk_queue_dma_alignment(rq, 511); - - /* Make sure we don't use bounce buffers. */ - blk_queue_bounce_limit(rq, BLK_BOUNCE_ANY); } static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size,